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i think setting up t/a would be the last you do in this tuning process , i think of it as more of a band aid then a tuning step ,
 

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Besides installation, time alignment can give you the most dramatic results. See my signature and the results people got from time alignment.
 

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Thanks for reviving this thread Optimaprime. I would have missed it otherwise and it's just what I was looking for.
 

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Ok so I've been meaning to try this but I had one doubt and kept putting off. Maybe this is a stupid question but I'm willing to take the chance!

I currently have 4 inch comps with the supplied crossovers. No problem I can just reverse the phase at the crossover for the mids and the tweets.

I also have 8 inch midbasses under the seats and I use the electronic crossover in my DQX. The dqx doesnt have a phase inverter. So where can I change the polarity of the midbass? Does it matter if I change it at the amp because I don't want to remove my seats.

I know its a dumb question I'm guessing it wouldnt make a difference if its at the amp or at the woofer. I didnt know if the electronic crossover would mess me up somehow.

Thanks
 

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Ok so I've been meaning to try this but I had one doubt and kept putting off. Maybe this is a stupid question but I'm willing to take the chance!

I currently have 4 inch comps with the supplied crossovers. No problem I can just reverse the phase at the crossover for the mids and the tweets.

I also have 8 inch midbasses under the seats and I use the electronic crossover in my DQX. The dqx doesnt have a phase inverter. So where can I change the polarity of the midbass? Does it matter if I change it at the amp because I don't want to remove my seats.

I know its a dumb question I'm guessing it wouldnt make a difference if its at the amp or at the woofer. I didnt know if the electronic crossover would mess me up somehow.

Thanks
Switch at the amp if that's easiest to reach. It won't make any difference.
 

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Just to update. I was able to go through all the steps, although I'm still fine tuning for tonality.

And I have to say I'm really happy with the results.

I'm really happy I came across this thread. Thanks for posting!
 

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I just got finished this procedure and all I can say is wow!! Eq is still flat and it never sounded better!! I am in the car now and I can't stop listening. I did perform time alignment prior to this. Thanks.
 

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Forgive me for resurrecting an older thread, but there is a lot of great info in here and I had a question about tuning with this method and how time alignment would affect things.

I assume that time alignment would affect the acoustic phase for individual speakers, correct? If so, when in this procedure would it be best to set the time alignment?
 

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I also want to apologize in advance for bumping an old thread. I was looking for a way to adjust phase prior to MS-8 calibration to give the processor an "easier" task. I have to say I tried using this method and was not able to hear any difference when only the tweeters, mids and woofers were playing, whether the polarity of one of the drivers was reversed or not. Sine the midbass drivers are under the seats, and only play to 120Hz anyway, there really was no "image" to make out at all. The tweeters and mids both had the female singer playing exactly at the respective driver side speaker, no matter what the polarity. Not sure why but I tried several times. Any ideas?
 

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I've tuned several vehicles and have only ran into what you described once.
The vehicle had speaker wiring issues, several speaker wire splices and solder joints with both active and passive crossovers.

I cleaned up the wiring, removed all splices, confirmed polarity and confirmed solder joint integrity at the passive crossovers.

Once that was done the vehicle would focus.

Nevertheless, it's my understanding that the MS8 wants the enter system to be wired in polarity.

I would run an in phase/out of phase track and note if the focus is the same in phase as out of phase. If so, given you can't change the focus by changing polarity, I would verify the system is wired properly.
 

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Thanks for your answer. I am fairly certain my wiring is sound. I should say that I confirmed polarities are correct with the JL audio app on the iPhone. Ran the MS-8 calibration and it sounded terrible. I flipped Polarity on the left side tweeter and midbass, recalibrated and the results are very satisfactory. However I am concerned that something is still off, because I could not get this method to work.

You kind of lost me in the last paragraph, but I will try to find such a track and report back. Any idea where I can find a track like this on the Internet?

I've tuned several vehicles and have only ran into what you described once.
The vehicle had speaker wiring issues, several speaker wire splices and solder joints with both active and passive crossovers.

I cleaned up the wiring, removed all splices, confirmed polarity and confirmed solder joint integrity at the passive crossovers.

Once that was done the vehicle would focus.

Nevertheless, it's my understanding that the MS8 wants the enter system to be wired in polarity.

I would run an in phase/out of phase track and note if the focus is the same in phase as out of phase. If so, given you can't change the focus by changing polarity, I would verify the system is wired properly.
 

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I have tried using a polarity checker and phase pulse test track before, and I have to admit that the results were not exactly so easy to determine. Getting the pulses to actually register consistently in the correct direction was difficult. Sometimes I would get a couple of cycles of + + + - to show correctly, but then it would start to read differently and make me question it.

Ultimately, I just gave up and used a 9 volt battery on my subs and midbass to visually confirm the direction of the speaker cone movement. Then I connected the 9 volt battery to the speaker wire and used a multimeter to confirm positive and negative leads in the cable run.

I have had mixed success using REW and impulse response measurements to determine phase angle. I say mixed because I had one day where everything measured well and I got good results for phase. But most of the time it's very hard to get clean phase measurements inside a car. There are so many reflections that it usually muddies up the readings.
 

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Thanks for your answer. I am fairly certain my wiring is sound.
Please don't be offended, but the guy with the splices and poor solder joints told me "my wiring is sound". :-D

After I spent hours uninstalling his wiring and tracing it from head unit to speaker, several issues...

I'm not saying yours is the same.

I should say that I confirmed polarities are correct with the JL audio app on the iPhone. Ran the MS-8 calibration and it sounded terrible. I flipped Polarity on the left side tweeter and midbass, recalibrated and the results are very satisfactory.
That's not how I read your original post.
I have to say I tried using this method and was not able to hear any difference when only the tweeters, mids and woofers were playing, whether the polarity of one of the drivers was reversed or not.
If you retuned with the MS8, you should not hear any different between a system wired in absolute phase and one that is not. Although some guys that are better tuners than I would say absolute phase is how a vehicle should be wired with DSP TA/phase correction.

However I am concerned that something is still off, because I could not get this method to work.

You kind of lost me in the last paragraph, but I will try to find such a track and report back. Any idea where I can find a track like this on the Internet?
subterFuse is correct, you could have physical boundary issues (early reflections) in your car still creating phase issues.

Recordings I like to use for in phase/out of phase are IASCA Setup CD, Autosound 2000 CDs, Chesky Setup CD or XLO Reference Recordings CD.

You may be able to purchase Chesky or XLO as an online down load.
You will have to do a search to find any of the IASCA or Autosound 2000 CD's.

XLO, which is intended for home systems, has several phase tracks and states to make your system sound as out of phase as possible by moving your speakers while playing the out of phase track. The more out of phase you get the system while playing an out of phase track, the more focus you will have when playing an in phase track.

In that we can't just move speakers in a car, you have to change the boundaries and/or your listening position.
 

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What I posted originally were the results without the MS-8 tune (processing turned off). Then when I did the auto-tune, it sounded horrible. Then I flipped polarities of driver side tweeter and mid-bass, retuned the MS-8, and it sounded great. Make sense?

Tonight I played pink (or white) noise from the Focal CD #2, track 3, which goes back and forth between in and out of phase. In phase sounds centered. Out of phase sounds scattered. So I guess that is a good sign. Then I turned MS-8 processing off and both in and out of phase white noise was playing near the sail panel on the driver side. I actually detected a little more of a "fullness" with the out of phase noise, and it was maybe an inch further to the right than the in phase noise, which was a little less full. Not sure how else to describe it. The differences were very small.
 
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